Are @Autowired or @Resource fields singletons?

Question

I'm maintaining an old application but am unfamiliar with Spring Framework. I'm working on a class that currently looks like this:

public class Foo {

    @Resource(name = "fb")
    private FooBar fb;

    @Resource
    private FooBar2 fb2;

    @Autowired
    private FooBar3 fb3 = null;

    ...
}

and an XML file that looks like this:

<beans xmlns="http://www.springframework.org/schema/beans" ... >
    <context:annotation-config/>
    ...
    <bean id="fb3" class="FooBar3"/>
    ...
</beans>

In some other method, the class Foo is instantiated:

void carryOutSomeFoobarring() {
    Foo f = new Foo();
    ...(use f)...
}

If carryOutSomeFoobarring is called at the same time from two different threads, there will, of course be two separate Foo instances of the local variable f. But will both instances of field f.fb refer to the same injected FooBar object? What about f.fb2 and f.fb3?

Answer 1

By default they're singletons. If the scope is changed to prototype, you get separate objects.